static void *try_ram_remap(resource_size_t offset, size_t size)
{
- struct page *page = pfn_to_page(offset >> PAGE_SHIFT);
+ unsigned long pfn = PHYS_PFN(offset);
/* In the simple case just return the existing linear address */
- if (!PageHighMem(page))
+ if (pfn_valid(pfn) && !PageHighMem(pfn_to_page(pfn)))
return __va(offset);
return NULL; /* fallback to ioremap_cache */
}
* memremap() - remap an iomem_resource as cacheable memory
* @offset: iomem resource start address
* @size: size of remap
- * @flags: either MEMREMAP_WB or MEMREMAP_WT
+ * @flags: any of MEMREMAP_WB, MEMREMAP_WT and MEMREMAP_WC
*
* memremap() is "ioremap" for cases where it is known that the resource
* being mapped does not have i/o side effects and the __iomem
- * annotation is not applicable.
+ * annotation is not applicable. In the case of multiple flags, the different
+ * mapping types will be attempted in the order listed below until one of
+ * them succeeds.
*
- * MEMREMAP_WB - matches the default mapping for "System RAM" on
+ * MEMREMAP_WB - matches the default mapping for System RAM on
* the architecture. This is usually a read-allocate write-back cache.
* Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
* memremap() will bypass establishing a new mapping and instead return
* MEMREMAP_WT - establish a mapping whereby writes either bypass the
* cache or are written through to memory and never exist in a
* cache-dirty state with respect to program visibility. Attempts to
- * map "System RAM" with this mapping type will fail.
+ * map System RAM with this mapping type will fail.
+ *
+ * MEMREMAP_WC - establish a writecombine mapping, whereby writes may
+ * be coalesced together (e.g. in the CPU's write buffers), but is otherwise
+ * uncached. Attempts to map System RAM with this mapping type will fail.
*/
void *memremap(resource_size_t offset, size_t size, unsigned long flags)
{
- int is_ram = region_intersects(offset, size, "System RAM");
+ int is_ram = region_intersects(offset, size,
+ IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
void *addr = NULL;
+ if (!flags)
+ return NULL;
+
if (is_ram == REGION_MIXED) {
WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
&offset, (unsigned long) size);
/* Try all mapping types requested until one returns non-NULL */
if (flags & MEMREMAP_WB) {
- flags &= ~MEMREMAP_WB;
/*
* MEMREMAP_WB is special in that it can be satisifed
* from the direct map. Some archs depend on the
* capability of memremap() to autodetect cases where
- * the requested range is potentially in "System RAM"
+ * the requested range is potentially in System RAM.
*/
if (is_ram == REGION_INTERSECTS)
addr = try_ram_remap(offset, size);
}
/*
- * If we don't have a mapping yet and more request flags are
- * pending then we will be attempting to establish a new virtual
+ * If we don't have a mapping yet and other request flags are
+ * present then we will be attempting to establish a new virtual
* address mapping. Enforce that this mapping is not aliasing
- * "System RAM"
+ * System RAM.
*/
- if (!addr && is_ram == REGION_INTERSECTS && flags) {
+ if (!addr && is_ram == REGION_INTERSECTS && flags != MEMREMAP_WB) {
WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
&offset, (unsigned long) size);
return NULL;
}
- if (!addr && (flags & MEMREMAP_WT)) {
- flags &= ~MEMREMAP_WT;
+ if (!addr && (flags & MEMREMAP_WT))
addr = ioremap_wt(offset, size);
- }
+
+ if (!addr && (flags & MEMREMAP_WC))
+ addr = ioremap_wc(offset, size);
return addr;
}
static void devm_memremap_release(struct device *dev, void *res)
{
- memunmap(res);
+ memunmap(*(void **)res);
}
static int devm_memremap_match(struct device *dev, void *res, void *match_data)
if (addr) {
*ptr = addr;
devres_add(dev, ptr);
- } else
+ } else {
devres_free(ptr);
+ return ERR_PTR(-ENXIO);
+ }
return addr;
}
void *devm_memremap_pages(struct device *dev, struct resource *res,
struct percpu_ref *ref, struct vmem_altmap *altmap)
{
- int is_ram = region_intersects(res->start, resource_size(res),
- "System RAM");
resource_size_t key, align_start, align_size, align_end;
struct dev_pagemap *pgmap;
struct page_map *page_map;
+ int error, nid, is_ram;
unsigned long pfn;
- int error, nid;
+
+ align_start = res->start & ~(SECTION_SIZE - 1);
+ align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
+ - align_start;
+ is_ram = region_intersects(align_start, align_size,
+ IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
if (is_ram == REGION_MIXED) {
WARN_ONCE(1, "%s attempted on mixed region %pr\n",
mutex_lock(&pgmap_lock);
error = 0;
- align_start = res->start & ~(SECTION_SIZE - 1);
- align_size = ALIGN(resource_size(res), SECTION_SIZE);
align_end = align_start + align_size - 1;
for (key = align_start; key <= align_end; key += SECTION_SIZE) {
struct dev_pagemap *dup;
for_each_device_pfn(pfn, page_map) {
struct page *page = pfn_to_page(pfn);
- /* ZONE_DEVICE pages must never appear on a slab lru */
- list_force_poison(&page->lru);
+ /*
+ * ZONE_DEVICE pages union ->lru with a ->pgmap back
+ * pointer. It is a bug if a ZONE_DEVICE page is ever
+ * freed or placed on a driver-private list. Seed the
+ * storage with LIST_POISON* values.
+ */
+ list_del(&page->lru);
page->pgmap = pgmap;
}
devres_add(dev, page_map);
/*
* 'memmap_start' is the virtual address for the first "struct
* page" in this range of the vmemmap array. In the case of
- * CONFIG_SPARSE_VMEMMAP a page_to_pfn conversion is simple
+ * CONFIG_SPARSEMEM_VMEMMAP a page_to_pfn conversion is simple
* pointer arithmetic, so we can perform this to_vmem_altmap()
* conversion without concern for the initialization state of
* the struct page fields.
struct dev_pagemap *pgmap;
/*
- * Uncoditionally retrieve a dev_pagemap associated with the
+ * Unconditionally retrieve a dev_pagemap associated with the
* given physical address, this is only for use in the
* arch_{add|remove}_memory() for setting up and tearing down
* the memmap.
projects / karo-tx-linux.git / blobdiff